Known surge protectors of the type mentioned discharge occurring voltage surges via the discharge contact of the mounting base into the metal mounting rail, which is also connected to an equalization potential such as the ground potential. Surge protectors with other designs are known that are connected directly via a cable that serves the purpose of discharging the voltage surge and that need to be connected to a locally present potential equalization device via a terminal point.
Depending on the installation conditions and the installation location, one of the two aforementioned designs for surge protectors is to be selected beforehand. Thus, the location and manner of installing the unit must already be determined when ordering the surge protector. Subsequent changes to the manner of installation, such as changing a discharge cable exiting the unit housing for rail mounting with the appropriate contacts is not possible; a different unit would be required in such cases.